Significance of Ice-loss to Landscapes in the Arctic: SILA (Inuit concept of the physical world and weather)

在过去的300万年里，冰盖在大约15%的地球陆地表面上前进和后退。这种冰川循环产生了很容易被化学反应改变的细粒沉积物。随着冰川退缩，地貌暴露，生态系统发展，沉积物发生反应，河水成分发生变化。在格陵兰岛西南部，冰川融水的溪流和冰川融水分离的非冰川溪流排放的水量相对于其流域面积相似，但由于不同的化学成分，它们向大气排放的温室气体和向沿海生态系统提供的营养物质的数量不同。 这些差异可能会影响气候，生态系统和人，突出了冰川环境变化的有效沟通，以公众的需要。发展有效的沟通技能是这个跨学科研究的一个组成部分，以评估生物，地球化学和水文过程如何控制冰川退缩时的河水成分。 这一认识将加强对过去冰川退缩的影响和对未来北极变暖的反应的评估。 项目成果将通过环境公民学进行分享，这是提高研究人员科学交流和领导技能的一个组成部分。 沉积物成分，暴露年龄，植物和微生物的殖民化，水的可用性，和流景观的连接被假设为不同的系统跨冰缘流域，从而控制风化程度，流地球化学，溶质和气体通量。 美国和格陵兰研究人员组成的跨学科小组将在从格陵兰冰盖到海岸的两个融化季节的流域对这一假设进行检验，他们将：a）测量非冰川河流流量、溶质和气体浓度和通量、微生物群落结构、植物群落分布、碳和营养物循环以及河流和推移质沉积物中的放射性同位素; B）维持自动化天气观测、灰尘收集和流化学记录器;以及c）执行流剂量实验。这些数据将揭示风化程度，生态系统特征，水文地球化学过程和流化学及其对冰缘流域溶质和气体通量的控制之间的反馈。在与格陵兰同事的合作中，研究结果将为环境公民计划提供种子，通过教师教育计划，在格陵兰高中适当的水平上制定和实施环境科学课程，并为格陵兰旅游业、格陵兰中学、该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准。

Ice sheets have advanced and retreated across approximately 15% of Earth’s land surface over the past three million years. This glacial cycling produces fine-grained sediments that are easily altered by chemical reactions. As glacial retreat exposes landscapes, ecosystems develop, sediments react, and stream water compositions change. In southwestern Greenland, streams draining glacial meltwater and non-glacial streams separated from glacial meltwater discharge similar amounts of water relative to their drainage areas, but because of distinct chemical compositions, they deliver differing amounts of greenhouse gases to the atmosphere and nutrients to coastal ecosystems. These differences may affect climate, ecosystems, and people, highlighting the need for effective communication of glacial environmental changes to the public. Developing effective communication skills is an integral part of this interdisciplinary study to evaluate how biological, geochemical, and hydrologic processes control stream water composition as glaciers retreat. This insight will enhance evaluations of the effects from past glacial retreat and responses to future Arctic warming. Project results will be shared through environmental civics, a component that will improve researchers’ science communication and leadership skills. Sediment compositions, exposure age, plant and microbe colonization, water availability, and stream-landscape connections are hypothesized to vary systematically across periglacial watersheds and thus control weathering extent, stream geochemistry, and solute and gas fluxes. This hypothesis will be tested in watersheds stretching from the Greenland Ice Sheet to the coast over two melt seasons by an interdisciplinary group of U.S. and Greenlandic researchers who will a) measure non-glacial stream discharge, solute and gas concentrations and fluxes, microbial community structures, plant community distributions, carbon and nutrient cycling, and radiogenic isotopes in stream and bedload sediment; b) maintain automated weather observations, dust collection, and stream chemistry loggers; and c) perform stream dosing experiments. These data will reveal feedbacks between weathering extent, ecosystem characteristics, biogeochemical processes, and stream chemistry and their controls on solute and gas fluxes from periglacial watersheds. In collaboration with Greenlandic colleagues, the results will seed environmental civics plans to develop and implement environmental science curricula at levels appropriate to Greenlandic high schools through a teacher-education program and to create educational materials for tourism in Greenland, Greenlandic secondary schools, and the Arctic Technology Center.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.